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the form of crevasses by virtue of brittle fractures in the ice mass. In order to understand the nature of the longitudinal stress in the area, resulted in the form of crevasses, the satellite imagery of the Polar ice sheet lying near the southern edge of
the SOPIM was studied and the crevasses are marked on the imagery in Arc-GIS
platform. The extent of the crevasses and their nature is marked.
3.6 Velocity Component
Glacier flows by virtue of the deformation of the ice and the nature of the bed over
which it slides. Glacier velocity therefore is equivalent of the deformation plus basal
sliding. The response of glacier ice to this stress is to deform and creep. Brittle
deformation is evident when glacier ice cannot creep fast enough to compensate the
driving stresses. The brittle failure in a glacier is expressed in the form of crevasses.
Though for this study, velocity is not computed for the movement of the Polar ice
sheet by the author, the existing information available from Sunil et al. (2007) was
studied here to understand the role of this dynamic factor. The GPS sites near DG
snout area exhibit low velocity (2.37 ± 0.01 ma
−1
) as compared to the eastern and
north-eastern side of the Schirmacher Oasis. The average direction of movement of
the glacier surrounding the Schirmacher Oasis is in the NE direction (Sunil
et al. 2007).
4 Results
4.1 Elevation
Based on the elevation measured from the Topographic map (Toposheet), the elevation of the Polar ice sheet lying to the south of the eastern part of the Schirmacher
Oasis was plotted in the area marked by yellow dashed rectangle represented in
Fig. 5. The highest elevation in the Schirmacher oasis is 233 m above m.s.l. But the
SOPIM in this region has less elevation. The elevation of the ice surface gradually
goes up towards south and southwest (Fig. 6a) and does not show any abrupt change
in the elevation. The elevation of the ice surface near the SOPIM remains around
120–160 m., but towards the southwest corner of the study area, the elevation
reaches about 470 m. The protruding parts of Veteheia nunatak over the Polar ice
sheet lying towards the southwest corner of the study area indicate the rise in the
elevation of the ice surface in its vicinity.
A. K. Swain
the form of crevasses by virtue of brittle fractures in the ice mass. In order to understand the nature of the longitudinal stress in the area, resulted in the form of crevasses, the satellite imagery of the Polar ice sheet lying near the southern edge of
the SOPIM was studied and the crevasses are marked on the imagery in Arc-GIS
platform. The extent of the crevasses and their nature is marked.
3.6 Velocity Component
Glacier flows by virtue of the deformation of the ice and the nature of the bed over
which it slides. Glacier velocity therefore is equivalent of the deformation plus basal
sliding. The response of glacier ice to this stress is to deform and creep. Brittle
deformation is evident when glacier ice cannot creep fast enough to compensate the
driving stresses. The brittle failure in a glacier is expressed in the form of crevasses.
Though for this study, velocity is not computed for the movement of the Polar ice
sheet by the author, the existing information available from Sunil et al. (2007) was
studied here to understand the role of this dynamic factor. The GPS sites near DG
snout area exhibit low velocity (2.37 ± 0.01 ma
−1
) as compared to the eastern and
north-eastern side of the Schirmacher Oasis. The average direction of movement of
the glacier surrounding the Schirmacher Oasis is in the NE direction (Sunil
et al. 2007).
4 Results
4.1 Elevation
Based on the elevation measured from the Topographic map (Toposheet), the elevation of the Polar ice sheet lying to the south of the eastern part of the Schirmacher
Oasis was plotted in the area marked by yellow dashed rectangle represented in
Fig. 5. The highest elevation in the Schirmacher oasis is 233 m above m.s.l. But the
SOPIM in this region has less elevation. The elevation of the ice surface gradually
goes up towards south and southwest (Fig. 6a) and does not show any abrupt change
in the elevation. The elevation of the ice surface near the SOPIM remains around
120–160 m., but towards the southwest corner of the study area, the elevation
reaches about 470 m. The protruding parts of Veteheia nunatak over the Polar ice
sheet lying towards the southwest corner of the study area indicate the rise in the
elevation of the ice surface in its vicinity.
A. K. Swain